Antibacterial fabric and composition

ABSTRACT

A fabric is saturated with a salt solution, such that when an electric current is applied to the fabric, the fabric exhibits a bactericidal ability. In another aspect, a salt solution includes a conductor, a humectant, a solvent, and a binder, where the conductor has an NaCl % w/w of between 3 and 11, the humectant has a glycerol % w/w of between 3 and 15, the solvent has a water % w/w of between 77 and 89 and the fixative includes a binder % w/w of between 0.01 and 2.0.

FIELD

The present disclosure relates to a fabric configured to be electrified to provide an antibacterial capability and a solution therefore.

BACKGROUND

It is known that electric currents have a bactericidal ability.

US Patent Publication 2021/0282475 discloses a device for preventing coronavirus transmission through the mouth and nose comprising a planar substrate comprising one or more biocompatible electrodes configured to generate at least one of a low level electric field or low level electric current, wherein the substrate is affixed to a surgical mask. However, the biocompatible electrodes are not capable of generating a bactericidal current.

U.S. Pat. No. 9,878,175 discloses a fabric for producing an induced electromagnetic field, comprising: a non-conductive base fabric having a first layer, a plurality of parallel, spaced apart electrically conducting carbon fibers interspersed in the first layer with none of the carbon fibers contacting each other, and a plurality of parallel, spaced apart electrically conducting silver fibers interspersed in the first layer with none of the silver fibers contacting each other, and with none of the silver fibers contacting the carbon fibers. However, the carbon and silver fibers are not capable of generating a bactericidal current.

Krishnamurthi, et al. “Microampere Electric Currents Caused Bacterial Membrane Damage and Two-way Leakage in Short Time,” Applied and Environmental Microbiology doi: 10.1128/AEM.01015-20, discloses that microampere electric currents cause significant membrane damage and allow two-way leakage of ions, small molecules and proteins.

There are applications where an electrified fabric would be advantageous for providing antibacterial capabilities.

SUMMARY

In at least one aspect, the disclosed embodiments are directed to a fabric impregnated with a salt solution, such that when an electric current is applied to the fabric, the fabric exhibits a bactericidal ability.

In another aspect, a fabric includes a conductive solution and a power supply coupled to opposite ends of the fabric to electrify the fabric to provide a bactericidal ability.

In still another aspect, a salt solution includes an NaCl % w/w of 7.0, a glycerol % w/w of 9.0, a water % w/w of 83, and a binder % w/w of 1.

In yet another aspect, a salt solution includes a conductor, a humectant, a solvent, and a binder, where the conductor comprises an NaCl % w/w of between 3 and 11, the humectant comprises a glycerol % w/w of between 3 and 15, the solvent comprises a water % w/w of between 77 and 89 and the fixative comprises a binder % w/w of between 0.01 and 2.0.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A-1D illustrate schematic examples of embodiments of the present disclosure.

DETAILED DESCRIPTION

The disclosed embodiments are generally directed to a fabric configured to be electrified for killing bacteria and a salt solution, that upon application of an electric current, exhibits a bactericidal ability.

FIG. 1A illustrates a schematic representation of an embodiment of the present disclosure. The electrified fabric 100 includes a power supply 102 coupled to a fabric 104. The power supply 102 may include a battery or other source of electricity and may optionally include regulation circuitry, for example, passive components, active components, or any combination thereof. The power supply 102 may be configured to provide power to the fabric 104, as a controlled current or voltage, or a controlled current and voltage. As an example, the power supply may be configured to provide a constant current of between 100-5000 μA to the fabric 104. The fabric 104 may be impregnated with a solution as described below in order to enhance the fabric's conductivity and may represent a resistive load, a reactive load or a combination resistive-reactive load.

FIGS. 1B-1D illustrate embodiments where one or more power supplies 106 may be used to provide current and voltage to the fabric 104. In FIG. 1B, a resistive load 108 may be coupled in parallel with the power supply 106 and the fabric 104 in order to maintain one or more of a particular current through or a particular voltage across, the fabric 104. In FIG. 1C, a resistive load 108 may be coupled in series with the power supply 106 and the fabric 104 in order to maintain one or more of a particular current through or a particular voltage across, the fabric 104. FIG. 1D illustrates an exemplary embodiment where a regulator may be coupled in series with the power supply 106 and the fabric 104 to provide one or more of a particular current through, or a particular voltage across, the fabric 104.

It should be understood that the power supply 106 may be a linear, switched, battery based, or any suitable power supply for applying power to the fabric 104.

Typical voltages may range from 1.5-3.0 volts and typical currents may range from 10-5000 μA. For purposes of the disclosed embodiments, a bactericidal current may be defined as a current that, over time, causes denaturation, lysis, or other damage that renders the bacteria unable to function, for example, 10 ma over 1 hour and 25 mA over 25 minutes.

Typical batteries used for the battery based power supply may have voltage ranges from 1.5-3 volts with typical mAh capacities from 200-1200 mAh. Some typical battery life examples are illustrated for a 1.5 volt battery with a 1030 mAh capacity:

-   -   1030 mAh÷0.100 milliamp through fabric≈10,300 hrs use (≈429         days)     -   1030 mAh÷0.200 milliamp through fabric≈5,150 hrs use (≈214 days)     -   1030 mAh÷0.500 milliamp through fabric≈2,060 hrs use (≈85 days)

As mentioned above, the fabric 104 may be impregnated with a solution in order to provide an electrical load and achieve a through current capable of destroying bacteria. Concentrations of components of the solution may be varied to achieve various electrical loads.

The fabric 104 may be a conductive or non-conductive fabric, made of natural and/or synthetic material, and may be woven and/or nonwoven. Typical fabrics may include cotton, rayon, polyester, silk, satin, denim, or any other suitable material. The fabric may be utilized in any suitable application, for example, face masks, air filters, clothing, compression sleeves for various body parts such as elbows, wrists, and knees, enclosures, pet beds, and heating pads.

For applications where skin will not be irritated, an exemplary moisture content may be up to or even greater than, 30%

The fabric 104 may be saturated with a salt solution composition with the following components and concentrations:

Lower Upper Item# Ingredients Function % w/w % w/w % w/w 1 Salt Conductor 7.0 3 11 2 Glycerol Humectant 9.0 5 15 3 Water Solvent 83.0 77 89 4 AH Binder Fixative/binder 1.0 .01 2.0

The components may be mixed together until the solution is homogenous and the fabric 104 may be saturated with the solution. The fabric 104 may then be dried until a desired moisture content is achieved.

An exemplary 2″×2″ (0.50 gram w/w) of dry fabric may absorb 1.5 grams of the solution.

The saturated fabric may exhibit the following electrical characteristics, where R represents a load, I is expressed in μA, V is expressed in volts, and R=V/I:

-   -   R=1.5 volts÷0.001 mA (100 μA)=1500Ω fabric+resistor load     -   R=1.5 volts÷0.002 mA (200 μA)=750Ω fabric+resistor load     -   R=1.5 volts÷0.005 mA (500 μA)=300Ω fabric+resistor load

The salt solution may include a conductor, a humectant, a solvent, and a binder. The conductor may include a salt, for example, NaCl, the humectant may include glycerol, the solvent may include water (H₂O), and the binder may be a casein based agent for intermediate fixation in laminate applications.

Table 1 shows different empirical studies A-D used to determine a preferred amount of glycerin to be used for the salt solution composition. Column D of the Components section represents an empirically determined amount of glycerin that results in the fabric feeling dry to the touch:

TABLE 1 Glycerin Determination A B C D Components (% w/w) NaCl 0.50 0.50 0.50 0.50 Glycerin 1.00 3.00 6.00 9.00 Binder 1.00 1.00 1.00 1.00 Water 97.50 95.50 92.50 89.50 DRY BASIS (in grams) Fabric 0.52 0.49 0.54 0.56 NaCl + Gly + AH 0.48 0.51 0.64 0.7 NaCl n/a 0.0001 0.0005 0.0007 Glycerin n/a 0.0006 0.006 0.0126 Binder n/a 0.0002 0.001 0.0014 Moisture n/a 4.50% 7.50% 10.50% Impedance O.L. 13.9 MΩ 1.4 MΩ 1.1 MΩ

The Dry Basis section shows the weight in grams of the components, the moisture content and the impedance of the fabric after drying

Table 2 shows different empirical studies E-H used to determine a preferred amount of sodium chloride to be used for the conductor of the salt solution composition, when the glycerin is held at a % w/w of 9. The target concentrations of the components are shown in column H:

TABLE 2 NaCl Determination Fabric Weight = 0.50 gram (2″ × 2″ swatch) E F G H Components (% w/w) NaCl 1.00 3.00 5.00 7.00 Glycerin 9.00 9.00 9.00 9.00 Binder 1.00 1.00 1.00 1.00 Water 89.00 87.00 85.00 83.00 DRY BASIS (in grams) Fabric 0.50 0.50 0.50 0.50 Fabric + NaCl + Gly + AH 0.69 0.74 0.78 0.8 NaCl + Gly + AH 0.19 0.24 0.28 0.30 NaCl 0.0019 0.0072 0.014 0.021 Glycerin 0.0171 0.0216 0.0252 0.027 Binder 0.0019 0.0024 0.0028 0.003 Moisture 11.00% 13.00% 15.00% 17.00% Impedance 440 KΩ 350 KΩ 330 KΩ 320 KΩ

The conductor may include, for example, one or more of organic and inorganic types of sodium, potassium, lithium salts of chloride, citrates, sulfates, phosphates, and any suitable conducting material.

The humectant may include, for example, one or more of glycerin, propylene glycol, polyethylene glycol (PEG's) butylene glycol etc. triethylene glycol, tripropylene glycol, PPGs, sorbitol (sugar alcohol), hexylene and butylene glycol, urea, and collagen.

The binder may include, for example, one or more natural binders such as glue and gelatin, synthetic binders such as TROL, SLN, IG, Acramin, etc.

IG Binders: Emulsion copolymer of vinyl acetate and butyl acrylate with a modified urea formaldehyde.

Ag Binders, which may be made by emulsion copolymerization of olifinic unsaturated monomers in an aqueous medium. The monomers may include, for example, acrylic acid ester (butyl or ethyl acrylate), styrene, acrylonitrile, vinyl chloride, asymmetric dichloroethane, vinyl acetate, and diolifine, such as butadiene

It is noted that the embodiments described herein can be used individually or in any combination thereof. It should be understood that the foregoing description is only illustrative of the embodiments. Various alternatives and modifications can be devised by those skilled in the art without departing from the embodiments. Accordingly, the present embodiments are intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.

Various features of the different embodiments described herein are interchangeable, one with the other. The various described features, as well as any known equivalents can be mixed and matched to construct additional embodiments and techniques in accordance with the principles of this disclosure.

Furthermore, some of the features of the exemplary embodiments could be used to advantage without the corresponding use of other features. As such, the foregoing description should be considered as merely illustrative of the principles of the disclosed embodiments and not in limitation thereof. 

What is claimed is:
 1. A fabric comprising a salt solution, such that when an electric current is applied to the fabric, the fabric exhibits a bactericidal ability.
 2. The fabric of claim 1, wherein the salt solution comprises a salt % w/w of 7.0, a glycerol % w/w of 9.0, a water % w/w of 83, and a binder % w/w of
 1. 3. The fabric of claim 1, wherein the salt solution comprises a conductor, a humectant, a solvent, and a binder.
 4. The fabric of claim 3, wherein the conductor comprises an NaCl % w/w of between 3 and
 11. 5. The fabric of claim 3, wherein the humectant comprises a glycerol % w/w of between 3 and
 15. 6. The fabric of claim 3, wherein the solvent comprises a water % w/w of between 77 and
 89. 7. The fabric of claim 3, wherein the fixative comprises a binder % w/w of between 0.01 and 2.0.
 8. The fabric of claim 1, wherein the electric current is regulated to approximately 100 microamps.
 9. A fabric comprising: a conductive solution; and a power supply coupled to opposite ends of the fabric to electrify the fabric to provide a bactericidal ability.
 10. The fabric of claim 9, wherein the power supply comprises a resistive load coupled in parallel with a battery.
 11. The fabric of claim 9, wherein the power supply comprises a resistive load coupled in series with a battery.
 12. The fabric of claim 9, wherein the power supply comprises a regulator coupled in series with a battery.
 13. The fabric of claim 9, wherein the salt solution comprises a conductor, a humectant, a solvent, and a binder.
 14. The fabric of claim 13, wherein the conductor comprises one or more of organic and inorganic types of sodium, potassium, lithium salts of chloride, citrates, sulfates, and phosphates.
 15. The fabric of claim 13, wherein the humectant comprises one or more of glycerin, propylene glycol, polyethylene glycol (PEG's) butylene glycol etc. triethylene glycol, tripropylene glycol, PPGs, sorbitol (sugar alcohol), hexylene and butylene glycol, urea, and collagen.
 16. The fabric of claim 13, wherein the solvent comprises water.
 17. The fabric of claim 13, wherein the binder comprises one or more natural binders, one or more synthetic binders, or an emulsion copolymer of vinyl acetate and butyl acrylate with a modified urea formaldehyde.
 18. A salt solution comprising an NaCl % w/w of 7.0, a glycerol % w/w of 9.0, a water % w/w of 83, and a binder % w/w of
 1. 19. A salt solution comprising a conductor, a humectant, a solvent, and a binder.
 20. The salt solution of claim 19, wherein the conductor comprises an NaCl % w/w of between 3 and
 11. 21. The salt solution of claim 19, wherein the humectant comprises a glycerol % w/w of between 3 and
 15. 22. The salt solution of claim 19, wherein the solvent comprises a water % w/w of between 77 and
 89. 23. The salt solution of claim 19, wherein the fixative comprises a binder % w/w of between 0.01 and 2.0. 